Registration Dossier

Ecotoxicological information

Toxicity to terrestrial arthropods

Currently viewing:

Administrative data

Endpoint:
toxicity to terrestrial arthropods: long-term
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study conducted on read-across material
Remarks:
Study performed to a guideline with minimal deviation.The read-across from MnSO4 to Mn(NO3)2 is justified on the following basis: both substances are very soluble in water hence bioavailable and both will release Mn2+ ions. Therefore, from an ecotoxicity standpoint, the nitrate or sulphate anions are not considered to have any influence on the effective toxicity of Mn2+ or any toxicity in their own right, so the anions can be disregarded. Therefore any effect will be related to the Mn2+ cation, and the data from MnSO4 ecotoxicity tests is regarded as a suitable surrogate for read-across
Justification for type of information:
See the read-across report attached in Section 13.
Cross-reference
Reason / purpose:
other: Read-across target
Reference
Endpoint:
toxicity to terrestrial arthropods: long-term
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study conducted on read-across material
Justification for type of information:
See the read-across report attached in Section 13.
Reason / purpose:
read-across source
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
2 444 mg/kg bw
Conc. based on:
other: Mn
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1 067 mg/kg bw
Conc. based on:
other: Mn
Basis for effect:
reproduction

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
2002

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
ISO 11267 (Inhibition of Reproduction of Collembola by Soil Pollutants)
Deviations:
yes
Remarks:
The method was adapted for use with natural soils
GLP compliance:
not specified
Application method:
soil

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): MnSO4·H2O
- Lot/batch No.: Stock #33341 Lot#H09J07

Sampling and analysis

Analytical monitoring:
yes

Test substrate

Details on preparation and application of test substrate:
The soil was a natural soil containing 1.2% organic matter.

Test organisms

Test organisms (species):
Folsomia candida
Animal group:
Acari (soil-dwelling predatory mite)

Study design

Study type:
laboratory study
Limit test:
no
Total exposure duration:
28 d

Results and discussion

Effect concentrationsopen allclose all
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
2 444 mg/kg bw
Conc. based on:
other: Mn
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1 067 mg/kg bw
Conc. based on:
other: Mn
Basis for effect:
reproduction

Any other information on results incl. tables

The natural background Mn concentration determined in the negative control treatment was 94 mg kg-I. Total extractable Mn concentrations (in excess of background) in the experimental treatments ranged from 99 to 140% and averaged 111% of nominal. Exchangeable Mn fraction expressed as percent of total concentration increased with increasing soil Mn loads.

Range finding test:

Manganese sulphate monohydrate (MnSO4·H2O) was used to conduct a range finding test. Adult survival and juvenile production decreased significantly at 5,000 mg/kg. There were no juveniles above the 5,000 mg/kg treatment concentration.

Definitive test:

Manganese did not affect (P = 0.168) adult springtail survival at the 1667 mg/kg concentration. Adult survival was significantly reduced (P = 0.0001) at 2444 mg/kg. The bounded NOEC for juvenile production was 1067 mg/kg (P=0.070). The bounded LOEC for juvenile production was 1100 mg/kg (P=0.025). No juveniles were produced in 2444 mg/kg treatment. The

EC20 and EC50 values for Mn for juvenile production were 1209 and 1663 mg/kg, respectively.

Table 1: Nominal and measured concentrations of manganese

Nominal (mg/kg)

Measured (mg/kg)

Corrected recovery (%)

0

94

0

287

386

102

500

633

108

695

1067

140

966

1100

104

1343

1667

117

1867

2444

126

2594

2836

106

3606

3667

99

5056

5056

99

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The lowest NOEC was 1067 mg/kg for reproductive effects. The read-across from MnSO4 to Mn(NO3)2 is justified on the following basis: both substances are very soluble in water hence bioavailable and both will release Mn2+ ions. Therefore, from an ecotoxicity standpoint, the nitrate or sulphate anions are not considered to have any influence on the effective toxicity of Mn2+ or any toxicity in their own right, so the anions can be disregarded. Therefore any effect will be related to the Mn2+ cation, and the data from MnSO4 ecotoxicity tests is regarded as a suitable surrogate for read-across